Magnetism, magnetocaloric effect and positive magnetoresistance in Fe-doped antipervoskite compounds SnCMn 3−xFe x ( x=0.05–0.20)

Abstract

The effects of Fe substitution on the structure, magnetic properties, magnetocaloric effect and positive magnetoresistance (MR) effect in antipervoskite compounds SnCMn 3− x Fe x ( x=0.05–0.20) have been investigated systematically. Partial substitution of Fe for Mn leads to the monotonic reduction in both the Curie temperature T C and saturated magnetization ( M S ). It can be attributed to the reduction of electronic density of state at the Fermi energy by Fe-doping. The maximum values of magnetic entropy change (−Δ S M ) and positive MR gradually decrease as x increases, due to the broadening of magnetic phase transition. The refrigerant capacity increases initially with x≤0.05, then decreases gradually as x increases further, which is suggested to originate from the competition between the decreasing −Δ S M and broadening temperature span. Our result indicates that the chemical doping on Mn site is an effective method for manipulating the properties of antiperovskite compounds AXMn 3.